Dead Ad Blue Pump and Faulty NOX Sensor Woes

[justyakking]

Just thought I share my experience with a dead Ad Blue Pump and faulty front NOX sensor, and hope some one can benefit from it.

So to get you up to speed mine is a W213 E220D 66 Plate. 205k on the clock. MOT had just expired and with EML on, I knew it would be a straight fail as emissions will be out of whack.

EML came on and at first I was able to reset and it would run for a while and come back on. So when it came back on more persistently, I took it in to dealers to get the code looked at. There was no lack of power or performance. I had full use of the revs, engine was responsive and still getting a good 60mpg on a 35mile run.

So they diagnosed NOX sensors was faulty and needed replacement. £120 plus vat for them to tell me what I already know. Since car was high mileage, they would not replace them under warranty. So to replace both sensors they quoted £800 + VAT and I was informed "they would have to code them into the computer". However, there is a nationwide shortage of these NOX sensors....not because its a design fault but merely that the suppliers are not making enough to satisfy the market demand bullshit. In the diagnostics, they said there were error codes coming from the Ad Blue tank and that they would need the car for another diagnostics (another £120 plus vat) to get to the root cause as fixing the NOX sensors require the AD Blue system upstream to be working normally. So when I got back into the car, I thought I get a read on the Ad Blue from the instrument panel and I got the dreaded "Cannot Read Levels" error. Fortunately, there was no countdown in miles before shutdown but since my MOT had run out, I had no choice but to get it fixed.

So I took car down to my local mechanic and his kit diagnosed an open circuit in the Ad Blue Pump and also an open circuit on the front sensor. The rear sensor was fine. Rang up a few Mercedes Parts Dept and they wanted £450 plus Vat for the NOX Sensor and £980 plus VAT for the tank. So I would be looking at around £2.5 - £3k to fix it and besides, they did not have any NOX sensors, I would have to wait till some become available and car could be out of action till autumn.

So I got my mechanic to strip the components off, got decent pictures of the part number and went hunting on ebay for them. The NOX sensor..A0009057108.. came off an S Class that had done 45k. I'd made sure the replacement was as identical as possible so got one that said Lunox-Sensor for £120 and that took 4 days to get to me. The AdBlue pump was unfortunately bonded to the tank so you can only replace the whole ****** tank...A2134706001...from Denso with EMITEC pump. There was none available in the UK so I had to buy a used one from Poland. Bought on the 9th and after a long delay at customs, it turned up on the 23rd...15th days.

So mechanic fitted the parts, filled tank up half way with ad blue. Fired it up, plugged in his diagnostics...cleared down the codes and had the engine running fine, he then serviced it, took car for it's MOT and it passed with a couple of tyre advisories. He didn't have to code anything in. Just clear the previous error codes and that was it. He charged me £525 to fit the parts, service and MOT'd it, all in. I've always taken my car to him for works and services so he could well be looking after me.

Since I'd been deprived of it for nearly 3 weeks(no car for 18 days!!!), I took it for a blast around some country lanes and so far no EML. Maybe I was lucky that the parts did not require coding in or maybe if you had similar parts, it doesn't require coding in and the dealer making it out that it needed coding in was designed to make you part with your hard earned cash.

Fingers and toes crossed the EML stays off. I'll come back to update you if it does.

It still wasn't cheap to fix but it was cheaper than taking it to the dealer. Hope this tale of woe helps someone out.

 

[bladecrazy]

hi, the new style sensors that mb were going to fit would require coding in, you have fitted the old style which are just plug and play but that part is superceeded by the new nox sensors.

 

[Pounder]

Just thought I share my experience with a dead Ad Blue Pump and faulty front NOX sensor, and hope some one can benefit from it.

So to get you up to speed mine is a W213 E220D 66 Plate. 205k on the clock. MOT had just expired and with EML on, I knew it would be a straight fail as emissions will be out of whack.

EML came on and at first I was able to reset and it would run for a while and come back on. So when it came back on more persistently, I took it in to dealers to get the code looked at. There was no lack of power or performance. I had full use of the revs, engine was responsive and still getting a good 60mpg on a 35mile run.

So they diagnosed NOX sensors was faulty and needed replacement. £120 plus vat for them to tell me what I already know. Since car was high mileage, they would not replace them under warranty. So to replace both sensors they quoted £800 + VAT and I was informed "they would have to code them into the computer". However, there is a nationwide shortage of these NOX sensors....not because its a design fault but merely that the suppliers are not making enough to satisfy the market demand bullshit. In the diagnostics, they said there were error codes coming from the Ad Blue tank and that they would need the car for another diagnostics (another £120 plus vat) to get to the root cause as fixing the NOX sensors require the AD Blue system upstream to be working normally. So when I got back into the car, I thought I get a read on the Ad Blue from the instrument panel and I got the dreaded "Cannot Read Levels" error. Fortunately, there was no countdown in miles before shutdown but since my MOT had run out, I had no choice but to get it fixed.

So I took car down to my local mechanic and his kit diagnosed an open circuit in the Ad Blue Pump and also an open circuit on the front sensor. The rear sensor was fine. Rang up a few Mercedes Parts Dept and they wanted £450 plus Vat for the NOX Sensor and £980 plus VAT for the tank. So I would be looking at around £2.5 - £3k to fix it and besides, they did not have any NOX sensors, I would have to wait till some become available and car could be out of action till autumn.

So I got my mechanic to strip the components off, got decent pictures of the part number and went hunting on ebay for them. The NOX sensor..A0009057108.. came off an S Class that had done 45k. I'd made sure the replacement was as identical as possible so got one that said Lunox-Sensor for £120 and that took 4 days to get to me. The AdBlue pump was unfortunately bonded to the tank so you can only replace the whole ****** tank...A2134706001...from Denso with EMITEC pump. There was none available in the UK so I had to buy a used one from Poland. Bought on the 9th and after a long delay at customs, it turned up on the 23rd...15th days.

So mechanic fitted the parts, filled tank up half way with ad blue. Fired it up, plugged in his diagnostics...cleared down the codes and had the engine running fine, he then serviced it, took car for it's MOT and it passed with a couple of tyre advisories. He didn't have to code anything in. Just clear the previous error codes and that was it. He charged me £525 to fit the parts, service and MOT'd it, all in. I've always taken my car to him for works and services so he could well be looking after me.

Since I'd been deprived of it for nearly 3 weeks(no car for 18 days!!!), I took it for a blast around some country lanes and so far no EML. Maybe I was lucky that the parts did not require coding in or maybe if you had similar parts, it doesn't require coding in and the dealer making it out that it needed coding in was designed to make you part with your hard earned cash.

Fingers and toes crossed the EML stays off. I'll come back to update you if it does.

It still wasn't cheap to fix but it was cheaper than taking it to the dealer. Hope this tale of woe helps someone out.

How much did you pay for the parts you purchased?